1. Field of the Invention
The present invention relates to a gate valve apparatus for a vacuum processing system and a semiconductor processing system including a plurality of process chambers. The term “semiconductor process” used herein includes various kinds of processes which are performed to manufacture a semiconductor device or a structure having wiring layers, electrodes, and the like to be connected to a semiconductor device, on a target object, such as a semiconductor wafer or a glass substrate used for an LCD (Liquid Crystal Display) or FPD (Flat Panel Display), by forming semiconductor layers, insulating layers, and conductive layers in predetermined patterns on the target object.
2. Description of the Related Art
In general, in manufacturing semiconductor devices, various processes, such as dry etching, sputtering, and CVD (Chemical Vapor Deposition), are repeatedly performed on a semiconductor wafer. Most of these processes are performed in a vacuum atmosphere within process chambers. The process chambers have transfer ports for transferring the wafer, which are airtightly closed by gate valve apparatuses during the processes.
Patent Document 1 (Jpn. Pat. Appln. KOKAI Publication No. 8-60374), for example, discloses a gate value apparatus of this type. For example, a transfer port is formed in a sidewall of a process chamber that can be vacuum-exhausted, and has a size to allow a wafer to pass therethrough. The transfer port is provided with a gate valve apparatus. During a process, the transfer port is airtightly closed by the valve body of the gate valve apparatus with, e.g., an O-ring interposed therebetween.
In conventional gate valve apparatuses, the structures of an elevating mechanism for moving a valve body up and down and a pushing mechanism for pushing the valve body against a transfer port are complicated and bulky. Consequently, they require a high equipment cost and a large installation space, and entail problems in reliability due to the complexity of the structure.